World food prices tracked by the United Nations’ Food and Agriculture Organisation have more than doubled in the past 10 years, while the US price of maize — a raw material for ethanol — has more than tripled.

Blaming the escalation of the price of some food products on speculation was “completely wrong” and politicians have failed to consider the link with energy markets, Mr Brabeck-Letmathe said at the Global Forum for Food and Agriculture in Berlin Sunday. “It is really unbelievable that when we have insufficient food in our world that we give it to cars.

“I plead very openly, no food for fuel. Give the food to people, but not to cars.

“Financial speculation is not responsible for the increase in food prices, it’s responsible for the volatility of food prices, but not the initial increase.”

Mr Brabeck-Letmathe described making biofuels from food crops as “nonsense”.

The agriculture ministers gathered in Berlin said in a statement agricultural investment in developing countries would need to be “substantially increased” to meet the food demand of 9-billion people in 2050. Average annual net investment in agriculture in those countries will have to be at least $83bn, according to estimates by the United Nations’ Food and Agriculture Organisation.

There was no estimate of current investment. Nonfood use of crops can affect food security, the ministers said.

Mozambique was demanding that private investors in agriculture make food production part of their plans as the country sought to become self-sufficient, its Agriculture Minister Jose Condungua Pacheco told the forum.

“The challenge is how private investment can collaborate with local policy. Any investment should take social responsibility, should share the risk with local people,” he said.